Portable power supply



FIG. 1 is a perspective view of a portable power supply showing my newdesign;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken line shown in the drawings of the portable power supply areincluded for the purpose of illustrating environmental structure andform no part of the claimed design.

CLAIM The ornamental design for a portable power supply, as shown anddescribed.